When the power meter access to the circuit under test, the current coil and the voltage coil there is alternating current flow, the two alternating current in their core, respectively, alternating magnetic flux; alternating magnetic flux through The aluminum plate in the aluminum plate in the induction of eddy current; eddy current in the magnetic field by the force of the role, so that the aluminum plate to get torque (active torque) and rotation. The greater the power consumed by the load, the greater the current through the current coil, the greater the eddy current induced in the aluminum pan, the greater the torque of the aluminum disk. That is, the size of the torque is proportional to the power consumed by the load. The greater the power, the greater the torque, the faster the aluminum plate rotates. When the aluminum plate is rotated, it is subjected to the braking torque generated by the permanent magnets. The braking torque is opposite to the direction of the active torque. The braking torque is proportional to the rotation speed of the aluminum plate. The faster the aluminum plate rotates, the braking torque is The bigger ones. When the active torque and brake torque to achieve a temporary balance, the aluminum plate will rotate at constant speed. The power consumed by the load is proportional to the number of revolutions of the aluminum plate. When the aluminum plate is turned, the counter is driven and the power consumed is indicated. This is the simple process of energy meter work.
Divided by principle
1. Energy meter is divided into induction and electronic two categories:
Induction energy meter uses the principle of electromagnetic induction to voltage, current, phase into magnetic moment, to promote the rotation of the aluminum disc, the disk axis (worm) drive gear drive the drum of the drum rotation, the process of rotation is The amount of time to accumulate the process. Therefore, the benefits of induction-type energy meter is intuitive, dynamic continuous, power loss does not lose data.
Induction of energy meter on the process requirements, materials involved in a wide range of metal, plastic, precious stones, glass, rare earth, etc., this product standards are related to the provisions and requirements, with low-cost low-quality materials instead of standard Specifications of the material is one of the major problems affecting the quality of the energy meter products, so like most commodities, the price is too low goods will not have a good quality assurance.
Induction of energy meter production process is complex, but already mature and stable, tooling equipment is also fully supported. The production environment has a high demand for temperature, humidity and air cleanliness. Nearly ten years in Hangzhou, Ningbo, Wenzhou and other places to develop the formation of the energy meter materials and parts market has a considerable scale, the formation of a distinctive China intensive production of the characteristics, which is where the production of energy meter in the market One of the main factors with price advantage.
Electronic energy meter using analog or digital circuit to get the product of voltage and current vector, and then through the analog or digital circuit to achieve energy metering function. As a result of the application of digital technology, time-sharing billing meter, pre-paid energy meter, multi-user power meter, multi-function energy meter have debut, and further meet the scientific electricity, reasonable demand for electricity.
Electronic energy meter in Jiangsu, Zhejiang, Shenzhen area of higher output, which is concentrated in the electronic products in this area is consistent, it is precisely because of the advantages of materials and parts of the market conditions, the formation of price competitiveness.
Currently on the whole, the induction type energy meter and electronic energy meter compared to the number of induction energy meter production for more. But the output of electronic energy meter has a clear upward trend.
2. According to the accuracy of measuring the power level, generally have 1 and 2 table: 1 level that the energy meter error does not exceed ± 1%; 2 that the energy meter error does not exceed ± 2%.
3. According to the additional function, how to rate the energy meter, pre-paid energy meter, multi-user power meter, multi-function energy meter, carrier energy meter. Multi-rate watt-hour meter or time-sharing watt-hour meter, complex rate table, commonly known as peak and valley table, is in recent years to meet the needs of peak-valley time-sharing needs of a means of measurement. It can be measured according to the predetermined peak, valley, peacetime, respectively, measuring the peak, low, flat power consumption, so that different periods of electricity consumption with different electricity prices, play a regulatory role in electricity prices, to encourage electricity customers Adjust the electricity load, shift peak fill the valley, the rational use of power resources, fully tap the hair, for, the potential of electrical equipment, electronic or mechanical and electrical energy meter; pre-paid energy meter commonly known as card table, The IC card can be inserted into the table can be controlled by the cost of electricity to prevent the arrears of electricity, electronic or mechanical and electrical energy meter; multi-user power meter a table for multiple users to use, for each user independent billing, Saving energy, and easy to manage the purpose, but also conducive to remote automatic centralized meter reading, is an electronic energy meter; multi-function energy meter set a number of functions, is an electronic energy meter; carrier power meter using power carrier technology for Remote automatic centralized meter reading, is an electronic energy meter.